Summary of Work: The disruption of the mouse gene encoding cPLA2 by homologous recombination is currently in progress. Mice deficient in functional cPLA2 will be generated by targeting the region of the gene encoding the active site of the enzyme at serine 228 which is known to be essential for enzymatic activity. A targeting construct is being electroporated into embryonic stem cells and targeted cells injected into 2.5 day old mouse blastocysts to produce chimeras. Mice deficient in cPLA2 will be used to determine the function of the enzyme in cancer and inflammation.